Develop System for Gas Turbine Duct Noise Cancellation

This effort will be to model, design, build, and test a prototype Active Noise Control (AMC) system for attenuating intake and exhaust noise produced by marine gas turbines. Currently, intake and exhaust duct linings and/or silencers reduce noise transmitted to spaces adjacent to the intakes and uptakes, including topside. Recent technology demonstrations, however, show that AMC-based quieting for gas turbine intake and exhaust noise can achieve comparable or better noise reduction than these traditional "passive" treatments with significantly reduced weight, space, and cost. The Phase I objectives are to: (1) develop an interactive noise simulation model for use an a shipboard AMC system design tool; (2) perform, for both intakes and exhausts, a feasibility evaluation of a primary and an alternate AMC system concept; and (3) determine the system design approach for Ph&" II. The critical issues that will be addressed in Phase I include: (1) AMC system performance and optimum locations; (2) AMC concept optimization for marine gas turbines; (3) the type of controller (feedback or feed forward) and error sensor; and (4) whether the controller needs to be adaptive to compensate for changes in operating conditions.- Phase I products will include: (1) a noise simulation model; and (2) a final report which presents the recommended system design approach.